absolutanne, I can only recommend the Rive Gauche! I have worn it a cpl of times now and it feels so comfortable no matter which way I wear it, as a messenger or as a tote.
I have decided to keep both the Muse and the RG. Yes, they`re quite similar, but they still feel different. The Muse is dressier, feels a little more mature (in a good way, not as in old!) and is just such an iconic shape, I couldn`t let it go!